Programming language

A programming language is an artificial language designed to express computations that can be performed by a machine, particularly a computer. Programming languages can be used to create programs that control the behavior of a machine, to express algorithms precisely, or as a mode of human communication.

The earliest programming languages predate the invention of the computer, and were used to direct the behavior of machines such as Jacquard looms and player pianos. Thousands of different programming languages have been created, mainly in the computer field, with many more being created every year. Most programming languages describe computation in an imperative style, i.e., as a sequence of commands, although some languages, such as those that support functional programming or logic programming, use alternative forms of description.

A programming language is usually split into the two components of syntax (form) and semantics (meaning) and many programming languages have some kind of written specification of their syntax and/or semantics. Some languages are defined by a specification document, for example, the C programming language is specified by an ISO Standard, while other languages, such as Perl, have a dominant implementation that is used as a reference.

FIVE STEPS OFf PROGRAMMING

1. Clarify Programming Needs

·                     Clarify objectives and users

·                     Clarify desired outputs

·                     Clarify desired inputs

·                     Clarify desired processing

·                     Double - check feasibility of implementing the program

·                     Document the analysis

2. Design the Program

·                     Determine program logic through top down approach and modularization, using a hierarchy chart

·                     Design details using procedure and/or flowcharts, preferably involving control structure. 

3. Code the Program

·                     Select the appropriate high-level programming language

·                     Code the program in that language following the syntax carefully 

4. Test the Program

·                     Alpha testing is the process of reading through the program in search of errors in logic. The second step is to run a diagnostic program to search for syntax or input errors.

·                     Beta testing involves using the program in the real world to see if it contains any bugs or other deficiency

5. Document and Maintaiin               Write user documentation

·                     Write operator documentation

·                     Write programmer documentation

·                     Maintain the program